Container refrigeration units have been used to provide cooling of the interior of a container for marine transportation, etc.
Patent Document 1 shows an example container refrigeration unit of this type. The container refrigeration unit is located at an opening of a container whose one end is open. That is, the container refrigeration unit has a casing which seals the open end of the container. The casing has, at its lower portion, an external accommodation space which faces the container exterior. A compressor, a condenser, an external fan, etc. are accommodated in the external accommodation space.
The casing also has, at its upper portion, an internal accommodation space which faces the container interior. This internal accommodation space is partitioned from the container interior space by a partition plate. The partition plate is supported by side stays provided at both lateral end portions on the interior side of the casing. Further, an internal fan, an evaporator, etc. are disposed in the internal accommodation space to form an air flow path for the air in the container.
During the operation of the container refrigeration unit, the air in the container is led to the air flow path in the internal accommodation space by the internal fan, and is cooled when it passed through the evaporator. The cooled air flows out from the air flow path, and is returned to the container interior. That is, the container refrigeration unit provides cooling and freezing of the container interior by cooling the air in the container when the air passes through the air flow path and circulating the cooled air.